Compound prosthesis



Jun 2 1965 w. J. PANGMAN COMPOUND PROS'IHESIS Filed April 11; 1962INVENTOR. Mum/11d ems/W4 vrorny United States Patent C a 3,1s9pz-1COMPOUND PROSTHESIS William J. Pangman, 734- Muirland Vista Way, LaJioila, Calif. Filed Apr. 11, 1%2, Ser. No. 186,669 6 Claims. (CH. 3 36)This invention relates generally to prostheses and, particularly, to animproved compound prosthesis to be implanted within the human body,particularly in the female breast.

It is common practice in the field of plastic surgery to enlarge thefemale breast by prosthetic implants. In other cases, large portions ofdiseased body tissue or body organs are removed, leaving voids which maybe filled by prosthetic implants. Such prosthetic implants providephysical support for the surrounding body tissue and organs and, in thecase of voids near the skin, preserve the outward appearance of thebody. In many instances, where cancerous, precancerous, or otherabnormal or damaged tissue is removed, it is possible in insert theprosthesis to be implanted through the same surgical incision used forremoving the tissue. The incision is then stitched and properly treated,making external detection of the implant extremely difficult, if notimpossible.

Among the problems involved in prosthetic implants are preseving thenatural softness and resiliency of the replaced body tissue andretaining the implant in position in the body. Thus, when the bodytissue which is built up or replaced by a prosthetic implant is soft andresilient, the prosthesis employed is preferably also soft and resilientin order to preserve the natural body characteristics. Use of prosthesishaving softness and resiliency matching as nearly as possible those ofthe replaced tissue is particularly important in certain areas of thebody, such as the female breast, wherein the entire mammary gland, forexample, may be replaced by a prosthetic implant. The importance ofretaining the implant in the proper position in the body is obvious.

Up to the present invention, the requirements of softness and resiliencyin a prosthetic implant have been met by the use of inert foam-typeplastic sponge materials, such as that manufactured under the trade namelvalon. In addition to being soft and resilent, and thereby ideallysuited to female breast implants, for example, inert sponge prosthesesare porous so that they absorb blood and other body fluids and becomeinvaded by blood vessels and living body tissues, with the result that asponge implant and the surrounding body tissue bcome so interwoven as topermanently retain the implant in position. Over a period of time, thesponge implant actually becomes an integral part of the body structureand can be removed only by surgical procedures.

The natural porosity of inelt sponge prostheses, while beneficial forthe reasons just discussed, renders the conventional one-piece spongeimplant useless after a period of time. The reason for this is thatblood vessels and other body cells and tissues eventually permeate themajor portion of or the entire body of such an implant. The majorinvading tissue is fibrous tissue which shrinks as it ages, therebycausing the implant to harden and shrink.

This invention provides an improved compound prosthesis having an outersponge shell Whose outer surface and major body portion are pervious toblood and to the ingrowth of blood vessels and fibrous tissue but whoseinner surface, while pervious to body fluids, is smooth and relativelyimpervious to the ingrowth of cellular structure. Within a centralcavity in this shell is a sponge core having a smooth outer surfacewhich, like the inner surface of the shell, is pervious to body fluidsbut relatively impervious to the ingrowth of cellular structure. Ac-

Zilfifififii Patented June 22, 1965 cordingly, when the prosthesis isimplanted in the body, the outer shell becomes invaded by body fluids aswell as by blood vessels and surrounding fibrous body tissue, wherebythe implant is permanently retained in position in the body. Therelatively impervious inner surface of the shell, however, prevents abarrier against invasion of living tissue completely through the shellinto the shell cavity. Accordingly, contact of such tissue with the coreand the consequential irritation of the tissue by the movements of thecore which occur during normal movements of the body are avoided.Moreover, the inner surface of the shell and the outer surface of thecore, in contact with the inner shell surface, both being relativelyimpervious to the ingrowth of cellular structure of the body, preventinvasion of the core by the cellular structure and thereby minimizeshrinking and hardening of the core.

An advantage of the present compound prosthesis is that in those caseswhere abnormal body reaction does cause undesirable shrinking orhardening of the core, the latter may be removed from the cavity withinthe shell and replaced with a soft new core by a simple secondaryoperation. If desired, the core of the present prosthetic implant mayalso be removed, the cavity defined by the shell enlarged by simplesurgical procedure, and a new larger core inserted into the cavity forthe purpose of enlarging a female breast, for example. This is aparticularly important advantage in restoring the contour of the breastfollowing radical removal of the latter because of malignant disease.

The inert sponge materials, such as Ival-on, from which the priorcompound prostheses have been fabricated are deficient from the medicalstandpoint in that their individual fibers are absorbent and, therefore,prone to infiltration by germs. Because of this infiltration of germsdirectly into the sponge fibers, infections occurring in priorprosthetic implants cannot generally be cured with antibiotics or othermedical treatments. As a result, most prior compound prosthetic implantswhich become infected must be surgically removed and replaced.

The present compound prosthesis is fabricated from an inert spongematerial whose fibers are not absorbent. Accordingly, the prosthesis canbe easily and completely sterilized directly in the operating suite sothat the incidence of infection in prosthetic implants is substantiallyreduced. Generally, any infections which do occur with the presentprosthetic implant can be cured by antibiotics.

A general object of this invention is, therefore, to provide an improvedcompound prosthesis of the character described.

A more specific object of the invention is to provide an improvedcompound prosthesis which, when implanted in the body, is partiallyinvaded by blood vessels and fibrous tissues, whereby the prostheticimplant is permanently retained in the proper position, and yet which isimmune to marked fibrosis and shrinking, whereby the prosthetic implantusually retains its softness and resiliency indefinitely.

Another object of the invention is to provide a compound prosthesis ofthe character described which is fabricated of an inert sponge materialwhose fibers are non-absorbent and, therefore, immune to infiltration bygerms, whereby the prosthesis can be easily and com pletely sterilizedin an operating room autoclave, thereby eliminating the necessity oftransporting a sterile prosthesis through an unsterilized area and theattendant possibility of reinfection of the prosthesis.

An object of the invention closely related to the foregoing object is toprovide a compound prosthesis of the character described in whichinfections occurring in the prosthesis after implanting of the lattercan usually be simply cured with antibiotics.

Yet another object of the invention is to provide a compound prosthesisof the character described whose components can be premolded in anydesired shape.

A further object of'the invention is to provide a compound prosthesis ofthe character described which is particularly useful as a female breastimplant.

The invention will now be described in detail by reference to theattached drawing, wherein:

FIG. 1 is a perspective view of a female breast prosthesis constructedin accordance with the invention;

FIG. 2 is an enlarged section through the prosthesis in FIG. 1; and

FIG-3 illustrates one method of fabricating the shell of the prosthesisin FIG. 1.

The prosthesis ltl illustrated in this drawing comprises an outer hollowbody or shell 12 and an inner core 14. The Wall of body or shell 12 isfabricated from an inert plastic foam sponge material whose fibers arenon-absorbe-n-t, such as one of the polyurethane foam plastics. Suchplastic foam sponge materials, as well known, are highly porous,containing throughout their interior a myriad of pores or openings whichopen through their normal exterior surfaces. The invention should not bethought of as limited to a shell made of a polyurethane foam, however,since other inert plastic sponge materials having nonabsorbent fibersmay be used. It may be possible, for example, to use a polyester foamwhich is treated with a chemical to render its normally hard fiberssufiiciently soft for use in a prosthesis. As will be seen, core 14 isalso fabricated of an inert sponge material which may be the same asthat used for the shell 12.

' Shell 12 and core 14; can be conveniently fabricated by molding to thedesired shape. For the particular use of the illustrated prosthesis, forexample, the shell and core are molded to the natural contour shown. Inactual practice, the illustrated compound prosthesis is made in severalsizes and shapes to meet various natural size and shape requirements.

Shell 12 comprises a forward curved wall portion 16 and a rear,generally flat wall portion 18. These wall portions define therebetweena chamber or cavity 20 containing the core 14. Shell 12 has a smoothinner surface or skin 21 which is relatively pervious to blood and otherbody fluids but relatively impervious to the ingrowth of blood vesselsand body tissue. The shell 12 is slit to' permit insertion of the coreinto the cavity. The slit 2?. for this purpose may be located at anyconvenient place in the shell, such as in the position shown. Afterinsertion of the core into the shell cavity, the slit 22 is stitched, asdepicted at 24.

Core 14 comprises an inner sponge body 26 and a smooth outer surface orskin 28 which, like the inner shell surface 21, is relatively perviousto blood and other body fluids but relatively impervious to the ingrowthof blood vessels and body tissue. As noted earlier, the sponge materialfrom which the core body 26 is made may be the some inert spongematerial used for the shell 12. The core body could, of course, be madeof a different inert sponge material than the shell. In any event, thecore body preferably comprises an inert sponge material whose fibers arenonabsorbent, whereby to prevent infiltration of germs directly into thesponge fibers. The use of sponge material having nonabsorbent fibers forboth the shell and core is also advantageous since the absence ofabsorbed fluid in the fibers results in a lighter prosthetic implant.

The smooth, relatively impervious surfaces or skins 21 and 2% of theshell and core, respectively, may be provided in various ways. Forexample, the skins may comprise an impervious coating of some suitableinert material, such as a silicone, plastic or other suitable inertcompound, which is sprayed on or otherwise applied to the surfaces ofthe shell and core. In the alternative, the surfaces or skins Z1, 28 maysimply comprise the smooth,

relatively impervious surfaces which are created by contact of the foamplastic from which the shell and core are made with the smooth walls ofa mold cavity.

The core 14 forms the main body of the present prosthesis, and it is theshape of the core which mainly determines the outer contour of the skinarea overlying the implanted prosthesis. In other words, it is the shapeof the core rather than the shape of the shell which is c-ritical. Forthis reason, the core is preferably made in the desired shape and theshell is shaped to fit the core. Thus, according to one method ofmanufacture ofthe present prosthesis, the core is molded to the desiredshape in a mold cavity and a rigid form having the exact shape of thecore is made. This form is placed on a fiat piece of foam plastic in theshape of the rear wall 18 of the shell 12 and which eventually formsthis wall. Another fiat piece of foam plastic of the proper shape, whichpiece eventually forms the forward wall 16 of the shell, is thenstretched over the form until the edge of the latter piece engages theedge of the first piece. These edges are then joined, as by forcing aheat sealing ring down over the form and the piece stretched thereoverto press the engaging edges of the plastic pieces into intimate contactand simultanously join these edges by heat sealing them together.

The heat sealing ring used in this method of fabrication is anincomplete ring so that the edges of the pieces will be left unjoined toform the slit 22 in the shell. After heat sealing, the form is removedthrough this slit.

As already noted-the shell 12 has a relatively impervious inner skin orsurface 21 which may comprise a suitable inert compound which is sprayedon, for example, or the skin may result from contact of the foam plasticmaterial of the shell with a mold cavity. In this latter connection,when the shell is fabricated with the aid of the form described above,the two flat foam plastic pieces which joined to form the shell may bemolded to the proper shape in flat mold cavities, or may be cut fromlarger sheets which are molded in mold cavities, having twice the depthof the desired wall thickness of the shell. During this molding process,contact of the foam plastic material with the wall of the mold cavitiesforms a smooth, relatively impervious skin on each side of the sheet orshaped piece. These sheets or pieces are then split edgewise to providetwo pieces or sheets, each of the proper thickness for the shell andeach having one smooth, relatively impervious surface which eventuallyforms the skin 21 of the shell. When the shell 12 is made by heatsealing the shell walls lid and 18 together about a form Sil as shown inFIG. 3, a smooth, impervious shell skin 21 can be formed by heating thecore with a coil 32. The coil leads 34 extend through the shell slit 2'2and the gap 36 in the heat sealing ring 33;

in use, the shell 12' and'core 1d of the prothesis are sterilized as aunit, that is, after the core has been inserted into the shell. Becausethe shell and core comprise a sponge material whose fibers arenonabsorbent and, therefore, immune to infiltration by germs, the shelland core can be adequately sterilized in the operating room autoclave,thereby eliminating the need of trans porting the sterile prosthesisfrom one place to another and the attendant possibility of reinfectionof the prosthesis.

In the case of a breast implant, the incision'is usually made at thelower base portion of the breast. After removal of the gland, if this isnecessary, the sterile prosthesis is compressed and inserted through theincision. Gnce located in the body cavity, the prosthesis springs backto its normal shape, pushing the patients breast or dermal layers intothe original shape. If desired or necessary, additonal sponge materialmay be inserted between the base of the core and the rear wall of theshell after the prosthesis has been inserted into the body in order tobuild up the prosthesis. The slit 22 in the shell is then stitched.After any other necessary surgical pro- :3 cedures have been completed,the patients incision is stitched in the usual manner.

Over a period of time, the sponge shell 12 becomes invaded by thesurrounding blood vessels and fibrous body tissues. In this Way, theprosthetic shell becomes so interwoven by the blood vessels and tissuesthat it becomes an integral part of the .body structure and is therebyeifectively retained in the proper position in the body. The skin 21 onthe inside of the shell prevents the ingrowth of cellular structure ofthe body into the shell cavity Where it would contact the core and beirritated by the movements of the core which occur during normalmovements of the body. Both the skin 21 on the shell and the skin 28 onthe core 14; prevent invasion of cellular structure into the core body26. Thus, the core usually retains its normal soft, resilient, flexiblecondition indefinitely so that a breast containing the presentprosthetic implant is or can be made substantially identical to a firmnormal healthy breast.

Since the fibers of the sponge material from which the prothesis is madeare immune to invasion by germs, any operating room infections which dooccur with the present prosthetic implant can usually be cured by theuse of antibiotics. Since the sponge fibers do not absorb body fluids,the prosthetic implant also remains lighter than a prosthesis made of asponge material with absorbent fibers.

An important advantage of the present compound prosthesis is that if thecore of an implanted prosthesis becomes undesirably hard or acquires aninfection which cannot be cured by medical treatment, the core can beremoved from and a new core replaced in the cavity 29 within the shell12 of the implanted prosthesis by means of a simple secondary operation.Moreover, at anytime, the core can be removed from an implantedproethesis, the cavity in the implanted shell enlarged by simplesurgical procedures, and a new larger core then replaced in the shell inorder to enlarge the implant. This is especially important, for example,in restoring the female breast contour following radical removal of abreast because of malignant disease.

Various modifications within the spirt and scope of the presentinvention will occur to those skilled in the art. While the inventionhas been described in connection with a breast operation, it is to beunderstood that compound prosthetic devices of this type may be employedas substitutes for a lung or other organs of the body with greatsuccess. The invention, therefore, is not to be thought of as limited tothe specific embodiment chosen for illustrative purposes.

What is claimed is:

1. A compound surgical prosthesis for insertion under the skin of thehuman body, comprising:

an exterior surrounding wall,

substantially the entire interior surface of said Wall bounded by asurface layer which is integral therewith and which is relativelyimpervious to cellular structure of the human body but relativelypervious to fluids in the human body, and the exterior thickness of saidwall outside said interior surface layer including substantially theentire exterior surface thereof being comprised of a foam-type resilientplastic surgical sponge material having a myriad of pores extendingthroughout it and opening through said exterior surface of the wall,whereby said exterior thickness of the Wall is relatively pervious to 6both said cellular structure and fluids of the human body,

there being a sealed closure in said wall,

a core substantially completely filling the space inside said Wall, and

substantially the entire exterior surface of said core having a surfacelayer which is relatively impervious to said cellular structure of thehuman body but relatively pervious to said fluids in the human body, andthe interior portion of said core inside said exterior surface layerbeing comprised of a foam-type resilient plastic surgical spongematerial having a myriad of pores extending throughout it, whereby thelatter is also relatively pervious to said body fluids.

2. A compound prosthesis according to claim 1 wherein:

the individual fibers of the surgical sponge material of both said bodywall and core are relatively impervious to said body fluids.

3. A compound prosthesis according to claim 1 wherein:

at least one of said impervious surface layers comprises a smoothsurface of the respective surgical sponge material itself wherein thesponge pores are substantially sealed.

4. A compound prosthesis according to claim 1 wherein:

at least one of said impervious surface layers comprises a thin layer ofa material different from and coated directly on the respective surgicalsponge material.

5. A compound prosthesis according to claim 1 wherein:

at least one of said surgical sponge materials comprises a polyurethanefoam plastic.

6. A compound surgical prosthesis for insertion under the skin of thehuman body, comprising: an exterior surrounding wall, substantially theentire interior surface of said surrounding wall being bounded by asurface layer which is relatively impervious to cellular structure ofthe human body but relatively pervious to fluids in the human body, andthe exterior thickness of said wall outside said interior surface layerincluding substantially the entire exterior surface thereof beingcomprised of a foam-type resilient plastic surgical sponge materialhaving a myriad of pores extending throughout it and opening throughsaid exterior surface of the wall, whereby said exterior thickness ofthe wall is relatively pervious to both said cellular structure andfluids of the human body, there being a sealed closure in said wall, acore substantially completely filling the space inside said wall, andsaid core being comprised of a foam-type resilient plastic surgicalsponge material having a myriad of pores extending throughout itsinterior, whereby the core is relatively pervious to said body fluids.

References Cited by the Examiner UNITED STATES PATENTS 2,636,182 4/53Freedman 336 2,698,436 1/55 Bernhardt 336 2,752,602 7/56 Wilhelm 3-362,842,775 7/58 Pangman 128-462 3,067,431 12/62 Kausch 3-36 LOUIS R.PRINCE, Primary Examiner. ADELE M. EAGER, Examiner.

1. A COMPOUND SURGICAL PROSTHESIS FOR INSERTION UNDER THE SKIN OF THEHUMAN BODY, COMPRISING: AN EXTERIOR SURROUNDING WALL, SUBSTANTIALLY THEENTIRE INTERIOR SURFACE OF SAID WALL BOUNDED BY A SURFACE LAYER WHICH ISINTEGRAL THEREWITH AND WHICH IS RELATIVELY IMPERVIOUS TO CELLULARSTRUCTURE OF THE HUMAN BODY BUT RELATIVELY PERVIOUS TO FLUIDS IN THEHUMAN BODY, AND THE EXTERIOR THICKNESS OF SAID WALL OUTSIDE SAIDINTERIOR SURFACE LAYER INCLUDING SUBSTANTIALLY THE ENTIRE EXTERIORSURFACE THEREOF BEING COMPRISED OF A FOAM-TYPE RESILIENT PLASTICSURGICAL SPONGE MATERIAL HAVING A MYRIAD OF PORES EXTENDING THROUGHOUTIT ANS OPENING THROUGH SAID EXTERIOR SURFACE OF THE WALL, WHEREBY SAIDEXTERIOR THICKNESS OF THE WALL IS RELATIVELY PERVIOUS TO BOTH SAIDCELLULAR STRUCTURE AND FLUIDS OF THE HUMAN BODY, THERE BEING A SEALEDCLOSURE IN SAID WALL,